Circuit breaker

Abstract

A circuit breaker for a low-voltage circuit is disclosed. In an embodiment, the circuit breaker includes a current conductor, assigned a measuring transducer for measuring the electrical current of the current conductor; a first filter connected to the measuring transducer; an analog/digital converter connected to the first filter; a second, high-pass filter connected to the analog/digital converter; and a digital integrator, connected to the high-pass filter and configured to determine the electrical current of the current conductor.

What is claimed is: 
     
       1. A circuit breaker for a low-voltage circuit, comprising: a low voltage circuit breaker having a series of:
 a current conductor, assigned a measuring transducer to measure electrical current of the current conductor; 
 a first filter connected to the measuring transducer; 
 an analog/digital converter, connected to the first filter; 
 a second filter, connected to the analog/digital converter; and 
 a digital integrator, connected to the second filter at a position downstream of the second filter and configured to determine the electrical current of the current conductor. 
 
     
     
       2. The circuit breaker of  claim 1 , wherein the digital integrator is a two-stage digital integrator. 
     
     
       3. The circuit breaker of  claim 1 , wherein the first filter is a low-pass or bandpass filter. 
     
     
       4. The circuit breaker of  claim 1 , wherein the second filter is a high-pass filter. 
     
     
       5. The circuit breaker of  claim 1 , wherein the second filter is a digital filter. 
     
     
       6. The circuit breaker of  claim 1 , wherein the first filter is a multistage filter. 
     
     
       7. The circuit breaker of  claim 1 , wherein the second filter is in the form of an infinite impulse response filter. 
     
     
       8. The circuit breaker of  claim 1 , wherein the second filter includes components configured to carry out a fast Fourier transform and an inverse fast Fourier transform. 
     
     
       9. The circuit breaker of  claim 2 , wherein the digital integrator includes a microprocessor, configured to carry out two-stage discrete integration. 
     
     
       10. The circuit breaker of  claim 9 , wherein the digital integrator is configured to carry out the integration using Simpson's formula. 
     
     
       11. The circuit breaker of  claim 9 , wherein the digital integrator is configured to carry out calculations with twice a strip width in a secondary calculation during the two-stage integration. 
     
     
       12. The circuit breaker of  claim 3 , wherein the second filter is a high-pass filter. 
     
     
       13. The circuit breaker of  claim 3 , wherein the second filter is a digital filter. 
     
     
       14. The circuit breaker of  claim 2 , wherein the first filter is a multistage filter. 
     
     
       15. The circuit breaker of  claim 3 , wherein the second filter is in the form of an infinite impulse response filter. 
     
     
       16. The circuit breaker of  claim 3 , wherein the second filter includes components configured to carry out a fast Fourier transform and an inverse fast Fourier transform. 
     
     
       17. The circuit breaker of  claim 1 , wherein the first filter is directly connected to the current conductor, the analog/digital converter is directly connected to the first filter, the second filter is directly connected to the analog/digital converter, and the digital integrator is directly connected to the second filter. 
     
     
       18. The circuit breaker of  claim 1 , wherein the low voltage circuit breaker is configured for voltages up to 1500 volt dc.